Effects of Aqualief® in Patients With Xerostomia as Consequence of Radiotherapy for Head and Neck Cancer

Overview

The treatment of xerostomia is aimed to increase existing saliva flow or replace lost secretions, the control of the state of oral health, the control of dental caries, and the treatment of possible infections. Therapy options in xerostomia depend on the presence of residual secretion or the absence of it. When residual secretory capacity is present, it is advisable to regularly stimulate the salivary glands by mechanical or gustatory stimuli as supportive oral care. Aqualief® is a food supplement based on carnosine and hibiscus. These two ingredients are mixed in specific proportions to form a pH buffering system which maintains the pH of the oral cavity at the proper value which is required for the regular secretion of saliva.

Xerostomia is the biggest and chronic side effect of the RT for head and neck cancer. To treat xerostomia different approach should be followed at the same time: to increase existing saliva flow or replace lost secretions, to control the state of oral health, to control dental caries and to treat possible infections18. When residual secretory capacity is present, it is advisable to regularly stimulate the salivary glands by mechanical or gustatory stimuli as supportive oral care. The salivary flow can be stimulated by the use of sugarless chewing gum or xylitol/sorbitol candy or through parasympathomimetic drug such as pilocarpine. Pilocarpine is a natural alkaloid that activates cholinergic receptors, authorized to treat xerostomia. Due to its main mechanism of action, pilocarpine has some muscarinic side effects19, especially vomiting, sweating, headache, increased urinary frequency, wheezing, watery eyes, nausea and gastrointestinal intolerance, hypotension, rhinitis, diarrhea, and visual disturbances. Pilocarpine has also some use restrictions that make it not prescribable to certain patients (patients with asthma, high blood pressure, heart diseases and in therapy with β-blockers cannot use pilocarpine because this drug is a nonselective antagonist of muscarinic receptors and, therefore, it can interfere with the cardiac and respiratory functions). Acupuncture seems to alleviate radio-induced xerostomia but it mechanism of action is not totally clear and systematic reviews indicate its efficacy as doubtful20,21. Other products are under investigation and their efficacy in xerostomia due to RT is still unclear. Aqualief® is a food supplement based on carnosine and hibiscus. These two ingredients are mixed in specific proportions to form a pH buffering system which maintains the pH of the oral cavity at the proper value which is required for the regular secretion of saliva. Aqualief® is designed as a mucoadesive tablet that will adhere to the cheek internal side, to have a prolonged action. It is expected to gradually release the ingredients over a period of at least two hours. Aqualief® is being tested in a clinical study on 70 subjects with grade 1-2 xerostomy enrolled at the Dental Clinic of the University of Insubria. The study is currently ongoing therefore results are not yet available. The aim of this clinical study is to evaluate if Aqualief® can be efficacious in the increasing of the saliva production in patients suffering for xerostomia as consequence of previous RT for head and neck cancer. To this purpose, this double blind cross over study has been designed: 100 patients will be treated for 8 days with Aqualief®/placebo and then, following a 10 days wash-out period, for further 8 days with placebo /Aqualief®.